Toward Atomically-Precise Bottom-up Nanomanufacturing

Ralph Merkle*

A new manufacturing technology looms on the horizon: molecular nanotechnology. Its roots date back to a 1959 talk by Richard Feynman in which he said, "The principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom. It is not an attempt to violate any laws; it is something, in principle, that can be done; but in practice, it has not been done because we are too big."

In the last few years the idea that we should be able to economically arrange atoms in most of the ways permitted by physical law has gained wider acceptance. This can be viewed as simply the culmination of a centuries-old trend: the basic objectives of manufacturing are lower cost, greater precision, and greater flexibility in what can be manufactured: as the decades have gone by, we've gotten better and better at it. The limit of low cost is set by the cost of the raw materials and energy involved in manufacture, the limit of precision is the ability to get every atom where we want it, and the limit of flexibility is the ability to arrange atoms in whatever patterns are permitted by physical law. While it seems unlikely that we will ever completely reach these limits, the objective of molecular nanotechnology is to approach them as closley as may prove feasible. Manufacturing costs should be low - a dollar a pound or less - almost regardless of what is being manufactured. Almost every atom should be in the right place - while background radiation limits this, error rates of a single atom out of place among many tens of billions seem feasible in properly designed structures under "normal" conditions. And finally, we should be able to make most structures that are consistent with physical law.

While the broad objective has gained acceptance, we have still not agreed on how best to proceed nor on exactly what this future technology will look like. The historically new technology of computers gives us the unprecedented opportunity to try out new ideas, new designs, and new concepts with remarkable precision and accuracy. This computational nanotechnology can shed light on what is possible today and in the future (and also on what doesn't work -- computational chemists are equally happy showing that a molecular machine works or to describe in loving detail how it breaks).

If we are to do what has not been done, if we are to build what has not been built, then the light that computational methods can shed on what is possible should be used to the fullest.